Suitable Specimen Types
- Serum
Specimen Transport
First class post to referral laboratory.Sample Processing in Laboratory
Centrifuge and separate serum. Perform total ALP analysis before sending to referral laboratory.Sample Preparation
Centrifuge sample and separate serum. Store separated serum at 4ºC prior to sending to referral laboratory.Turnaround Time
2 weeks from date received by referral laboratorySample Stability
4ºC
Alkaline Phosphatase (ALP) Isoenzymes (APISO)
General Information
Alkaline Phosphatase (ALP) in human serum originates from several sources including bone; liver; intestine and placenta. Because of the wide distribution, limited information can be obtained from a total ALP activity assay. The tissue source of elevated ALP in serum, however, can be determined by identifying the individual isoenzyme present in excess.
The individual ALP isoenzymes normally can be separated by electrophoresis according to charge differences. The separated ALP isoenzymes are visualised using a specific chromogenic substrate.
Patient Preparation
None
Notes
Test not required if total serum ALP is in the normal range.
PLEASE NOTE from 01/08/2012, ALP isoenzyme analysis is no longer performed in-house, specimens to be sent to referral laboratory. All requests will be vetted by the Duty Biochemist.
Reference Range
Reported as a comment:
ALP1 |
Predominantly liver isoenzyme present. |
ALP2 |
Predominantly bone isoenzyme present. |
ALP3 |
Both liver and bone isoenzymes are present in approximately equal concentrations. |
ALP4 |
Biliary isoenzyme also present. |
ALP5 |
Intestinal isoenzyme also present: this may indicate intestinal disease but also may occur in the absence of pathology in some individuals of blood group O and B after eating. |
ALP |
Alkaline phosphatase isoenzyme analysis is not indicated when the total alkaline phosphatase is not markedly raised. |
Specifications
- EQA Scheme?: No
-
EQA Status:
No EQA Scheme available